I have completed this little arena mission thing 8 times now. At the end once you have completed all 5 stages you get the best rewards in the game. Once you have found where to go there are two chests and a coffin or big box with ALOAD of loot. The first two times i completed this i could open all three chests and get all the loot.... But now i can only open and receive the two side (small) chests. I try to open the bigger one (placed in the middle) but i simply cannot. If someone else makes their way down to the treasure they can open all three and receive the loot. I should of gotten this middle chests 8 times but i have only had it 2... PLEASE FIX THIS BUG!